This invention relates to Radio Frequency (RF) radiation-free environments of various sizes which will reduce the signal strength of RF radiation therein. The net result will be a substantial signal strength reduction in order to create an RF-free environment so as to render wireless communications devices ineffective therein.
Wireless communications devices such as cell phones and pagers have become essential to everyday life. While wireless communications devices are of great benefit, they also have become an intrusion of privacy and an annoyance. For example, when attending the theater, patrons do not wish to have the performance interrupted by a ringing cell phone or pager. In certain situations, RF radiation may also interfere with commercial or industrial processes such as testing, medical diagnostics, or general telecommunications. For these reasons alone, the desirability of an RF radiation-free enclosure is evident.
Furthermore, although preliminary results are inconclusive, ongoing research suggests that active wireless telecommunications devices such as cell phones, Personal Communication System (PCS) phones, satellite phones and two-way pagers pose a health risk to the consumer. Technology still under development will likely lead to yield new and unique ways of utilizing the electromagnetic (EM) spectrum. Currently, the EM environment encompasses applications such as analog and digital cellular telephony, wireless data, wireless Local and Wide Area Networks (LAN""s and WAN""s), satellite voice and data, long and short-haul microwave communications, to name but a few. These and future such applications would only proliferate further, thereby increasing the general risk of RF radiation to the public at large.
Thus, there is a need to solve the problems created by these transmissions, and the present invention provides RF radiation-free environments of various sizes which will reduce the signal strength of RF radiation or transmissions therein.
The invention relates to a method of rendering telecommunication devices ineffective, which comprises creating a substantially radio frequency radiation-free environment by providing an interference generating pattern (xe2x80x9cIGPxe2x80x9d) adjacent the environment in a position between the environment and a source of radio frequency radiation signals so as to substantially reduce, or interfere with such signals thus preventing typical operation of the telecommunications devices.
The environment may be an enclosure having one or more walls and the IGP is provided on at least one wall. When the enclosure includes a ceiling and floor, the interference generating pattern may be provided upon at least one of the ceiling or floor. Generally, the IGP is provided as a paint, coating or building material onto both the walls and ceiling of the enclosure.
Another aspect of the invention relates to a radio frequency reducing building material that has an IGP associated with it in order to substantially reduce or interfere with radio frequency signals to prevent typical operation of telecommunication devices when the radio frequency reducing building material is positioned between a source of such signals and telecommunications devices. These building materials can include the IGP as a paint or coating on one or more surfaces of the material. The building material may be in the form of paper, cloth, plastic film, plywood, a cement or concrete structure, metal or plastic siding, glass, and wallboard or sheetrock. Alternatively, the IGP may be provided within the building material or beneath a protective covering or a paint or protective film so that the building material may be transported and handled without damaging the IGP.
The invention also relates to a substantially radio frequency radiation-free environment that includes an IGP adjacent thereto in a position between the environment and a source of radio frequency radiation signals so as to substantially reduce or interfere with such signals to prevent typical operation of telecommunication devices therein. Typically, the environment can be made by use of one or more of the building materials that are described herein.
When the enclosure is a building that includes exterior windows and doors, the IGP may be provided adjacent to or upon at least one of the windows or doors. To do so, the IGP may be provided upon a cloth, fabric or other building material that is located adjacent the windows or doors of the enclosure.
In another embodiment of the invention, the environment is a container or box having a top, bottom and sides each provided with the IGP.
The IGP is advantageously configured to attenuate radio frequency radiation in the range of 800 MHZ to 2400 MHZ, and to do so, includes compounds of silicon and carbon, such as silicon carbide. Advantageously, the IGP reduces the radio frequency signal by at least 20 to 30 dB. A plurality of IGPs can be superimposed to attenuate radio frequency radiation over the entire desired frequency range. For optimum performance or where a higher degree of shielding is required, multiple IGPs can be stacked or arranged throughout the thickness of the building material.